Key binding in wpf

I have 开发者_StackOverflowproblem with key bindings. I can't set key for "+". Can somebody help me, what should I write in xaml and what should I write in .cs ???

Keybindings can be set at the Window level, so in XAML you'd add...

<Window.InputBindings>
  <KeyBinding Command="YourCommand" Key="+" />
</Window.InputBindings>

I assume you know how to provide a Command with Window.CommandBinding.